TY - JOUR

T1 - Ordovician turbidites and black shales of Bennett Island (De Long Islands, Russian Arctic), and their significance for Arctic correlations and palaeogeography

AU - Danukalova, Maria K.

AU - Kuzmichev, Alexander B.

AU - Sennikov, Nikolai V.

AU - Tolmacheva, Tatiana Yu

N1 - Funding Information: This study has been carried out following the plans of the scientific research of the Geological Institute of RAS (for MKD, ABK, project no. 0135-2015-0020) and was supported by the Russian Foundation for Basic Research (ABK, MKD, grant nos 19-05-00926 and 14-05-31042; NVS, grant no. 18-0570035). We thank Thomas Hadlari and an anonymous reviewer for their helpful comments. Publisher Copyright: © 2020 Cambridge University Press. Copyright: Copyright 2021 Elsevier B.V., All rights reserved.

PY - 2020/8/1

Y1 - 2020/8/1

N2 - Bennett Island stands alone in a remote part of the Arctic and information on its geology is essential to ascertain relations with other terranes in order to restore the early Palaeozoic Arctic palaeogeography. Lower Palaeozoic sedimentary rocks throughout the island were studied thoroughly for the first time. The Ordovician section (> 1.1 km thick) comprises three units: Tremadocian, lowest Floian black shale (130-140 m); Floian, lower Dapingian carbonate turbidite (> 250 m); and Dapingian, lower Darriwilian siliciclastic turbidite (> 730 m). Ordovician deposits conformably overlie Cambrian rocks deposited within the Siberian shelf, as shown earlier. Most of the Ordovician succession was formed in a deep trough that received carbonate debris from a nearby carbonate platform and silicate material from a distant landmass located to the NE (present coordinates). The Bennett Island Ordovician rocks have much in common with those of both the Central and Northern Taimyr belts. It could be tentatively suggested that both belts merged at their eastern continuation in the vicinity of De Long Islands. The whole system probably extends further eastwards. The Ordovician facies patterns and faunal assemblages in the New Siberian Islands are notably similar to those of northwestern Alaska, where the same lateral transition from turbidites to shelf limestones was reported.

AB - Bennett Island stands alone in a remote part of the Arctic and information on its geology is essential to ascertain relations with other terranes in order to restore the early Palaeozoic Arctic palaeogeography. Lower Palaeozoic sedimentary rocks throughout the island were studied thoroughly for the first time. The Ordovician section (> 1.1 km thick) comprises three units: Tremadocian, lowest Floian black shale (130-140 m); Floian, lower Dapingian carbonate turbidite (> 250 m); and Dapingian, lower Darriwilian siliciclastic turbidite (> 730 m). Ordovician deposits conformably overlie Cambrian rocks deposited within the Siberian shelf, as shown earlier. Most of the Ordovician succession was formed in a deep trough that received carbonate debris from a nearby carbonate platform and silicate material from a distant landmass located to the NE (present coordinates). The Bennett Island Ordovician rocks have much in common with those of both the Central and Northern Taimyr belts. It could be tentatively suggested that both belts merged at their eastern continuation in the vicinity of De Long Islands. The whole system probably extends further eastwards. The Ordovician facies patterns and faunal assemblages in the New Siberian Islands are notably similar to those of northwestern Alaska, where the same lateral transition from turbidites to shelf limestones was reported.

KW - conodonts

KW - depositional environments

KW - early Palaeozoic

KW - graptolites

KW - New Siberian Islands

KW - palaeoreconstructions

KW - Siberia

KW - SERIES

KW - DETRITAL ZIRCON AGES

KW - STAGE

KW - GSSP

KW - NORTHERN

KW - SUCCESSIONS

KW - CONODONTS

KW - SIBERIAN ISLANDS

KW - DEPOSITS

KW - SEVERNAYA ZEMLYA

UR - http://www.scopus.com/inward/record.url?scp=85077996754&partnerID=8YFLogxK

U2 - 10.1017/S0016756819001341

DO - 10.1017/S0016756819001341

M3 - Article

AN - SCOPUS:85077996754

VL - 157

SP - 1207

EP - 1237

JO - Geological Magazine

JF - Geological Magazine

SN - 0016-7568

IS - 8

ER -